Hello, it is nice to meet you.Okay, this is a lot of back and forth, and I seem to get the gist between you @GWH and @Soyeong and I think I see the fundamental misunderstanding. So let me start off by saying, what Soyeong says is correct (although I disagree with some minute details, but the gist is correct). So let me explain and I'll do my best to be thorough and maybe I can resolve this misunderstanding.
Jesus saves us from our sin (Matthew 1:21) and it is by the Torah that we have knowledge of what sin is (Romans 3:20), so while we can't earn our salvation even as the result of having perfect obedience to the Torah, there is nevertheless an intrinsic connection between our gift of salvation and our gift of getting to experience being a doer of the Torah. Jesus graciously teaching us to experience being a doer of the Torah is intrinsically the way that he is giving us his gift of saving us from not being a doer of it.Back in the day around the time of Jesus, Jews believed that following all the law is what saved you. Meaning, if you are perfect in the law, that is what mattered.
In Psalm 119:29-30, he wanted to put false ways far from him, for God to be gracious to him by teaching him to obey the Torah, and he chose the way of faith by setting it before him, so this has always been the one and only way of salvation by grace through faith in Christ alone. In Titus 2:11-13, the content of our gift of salvation is described as being trained by grace to do what is godly, righteous, and good, and to renounce doing what is ungodly, so we are not extrinsically required to have first done those works in order to earn our salvation as the result and we are not extrinsically required to do those works as the result of having first been said, but rather we are intrinsically required to be a doer of those works because God graciously teaching us to experience being a doer of them is part of the content of His gift of salvation.
The issue of the way to acquire righteousness is different than the issue of what it means to be righteous. The only way to become righteous is through faith apart from being required to have first done enough righteous works in order to earn it as the result, but what it means to be righteous is to be a doer of righteous works in obedience to the Torah (1 John 3:4-7, Isaiah 51:7). We can't earn our righteousness even as the result of having perfect obedience to the Torah (Romans 4:1-5), but being a doer of the Torah is what we get to experience by being given the gift of righteousness through faith. Paul also affirmed in Romans 2:13 that only the doers of the Torah will be declared righteous, so there is a reason why our righteousness requires us to choose to be doers of the Torah other than in order to earn it as the result, namely faith insofar as the faith by which we are declared righteous apart from works also upholds the Torah (Roman 3:28-31).The Law defined what God considered righteous. It's like a mirror to show us really how dirty we are in comparison to the standard that God set. So to simplify:
Following the Law = Righteousness
Breaking the Law = Sin
When Christ entered the picture, the understanding of salvation went back to Abraham's time, who declared: "He (Abraham) believed in Adonai, and he credited it to him as righteousness." Which was always the basis for salvation. Salvation has always been through belief. When Jesus came, he said he came to save the Jews who walked away from that belief and relied on their own righteousness to follow the Torah/Law. But it's always been grace. (There's more nuance to this but I'm trying to not make it convoluted.)
While it is true that Abraham was declared righteous because he believed God (Genesis 15:6), it is also true that he was a doer of righteous works because he believed God (Genesis 18:19) and that he offered Isaac because he believed God (Hebrews 11:17), so the faith by which he was declared righteous was also embodied through his works, but he did not earn his righteousness as the result of his works. In James 2:21-24, Abraham was declared righteous by his works when he offered Isaac, his faith was active along with his works, and his faith completed his works, so he was declared righteous by his works insofar as they embodied his faith but not insofar as they were earning it as a wage.
To believe in God is to have the goal of growing to be in His image through embodying His character traits. Similarly, the Son is the radiance of God's glory and the exact likeness of His character (Hebrews 1:3), which he embodied through his works by setting a sinless example for us to follow of how to walk in obedience to the Torah, so to believe in Christ is to make it our goal to be more like him. For example, the way to believe that God is compassionate is by being compassionate (Luke 6:36), the way to believe that God is holy is by being a doer of His instructions for how to be holy as He is holy (1 Peter 1:16), and so forth, so we embody what we believe to be true about God through our works (James 2:18) and it is by this faith alone apart from works done in order to earn them as the result that we acquire righteousness and the other character traits of God. This is also why the Bible frequently connects our belief in God with our obedience to Him, such as with Revelation 14:12, where those who kept faith in Jesus are the same as those who kept God's commandments.
In Matthew 7:21-23, Jesus said that only those who do the will of the Father will enter the Kingdom of Heaven in contrast with saying that he would tell those who are workers of lawlessness to depart from him because he never knew them, so the reason why our entrance into the Kingdom of Heaven requires us to do the will of the Father by being workers of lawfulness in not in order to be good enough to earn our way there as the result, but because that is the way to know Jesus through embodying His character traits.Now, let's get more nuanced because I think this is where the fundamental misunderstanding is. When it comes to the law, we are still expected to follow it. God's grace is never a license to sin, or to disregard God's righteous rules. It's literally impossible to follow them all, but God still expects you to try. Because either you are a slave to righteousness (the law) or a slave to sin (lawlessness). You cannot serve 2 masters. That does not mean the law gets you to heaven, it just means God's expectations is that ALL His children are still, to the best of their ability, supposed to follow the law.